Adrenal neoplasms include benign and malignant tumors of the adrenal gland. Adrenocortical adenomas are benign tumors of the adrenal cortex and are extremely common. In contrast, malignant adrenal tumors such as adrenocortical carcinomas (ACC) are rare malignancies that have an annual incidence of 0.5-2 cases per million.
ACC has a very poor prognosis with only a 15-45% survival at 5 years. The incidence of ACC is highest in the fifth and sixth decade of life, however a high incidence of ACC has been found in children in southern Brazil which was associated with a germline mutation in p53. Over half of ACC are considered functional (producers of steroid hormones) when excess hormones are produced and Cushing's syndrome is the most common clinical manifestation. The majority of ACC cases are sporadic, however, several genetic syndromes have been associated with ACC including Beckwith-Wiedemann and Li-Fraumeni syndromes, Carney complex, familial adenomatous polyposis, congenital adrenal hyperplasia, and multiple endocrine neoplasia type 1. Without the clear presentation of local invasion or distant metastasis, the diagnosis and pathological distinction between benign and malignant adrenocortical tumors can be difficult. Histologically, the 9 Weiss parameters (0-9 score) are commonly used for diagnosis, with Weiss scores of ≦2 being considered benign and ≧3 malignant. However, given the subjective nature of the Weiss histologic features, particularly in regards to scores of 2-3 that are of indeterminate classification and the most common group of adrenocortical tumors, there is a need for better diagnostic tools for assessing adrenocortical tumors, preoperatively and as an adjunct to routine histopathology.